The present invention relates to safety needle holders of the kind currently used i.a. in intravenous access devices such as disposable blood collection devices.
Such a needle holder is known, for instance from U.S. Pat. No. 5,067,490, U.S. Pat. No. 5,070,885 and FR-A-2 686 242.
U.S. Pat. No. 5,067,490 discloses a shielded safety syringe comprising a cylindrical outer sleeve and an inner needle carrier holding a double-pointed needle in fluid communication with a vacuum tube and slidable within the outer sleeve between two positions. In the first, distal position, the needle projects from the outer sleeve and is exposed for drawing blood. In the second, proximal position, the needle is retracted within the outer sleeve. The needle carrier is releasably held in the first position, so that it can be readily moved into the second position after use. After the needle has been retracted into the sleeve, the carrier is locked in its second position to prevent health care workers from coming into accidental contact with the used needle.
The arrangement disclosed in U.S. Pat. No. 5,070,885 provides for a double-ended cannula to be retracted within a respective sleeve or barrel for storage and disposal. The cannula is attached to the device immediately prior to use by being threaded into an aperture formed in a movable disc disposed within the barrel and rotated to a locked operating distal position for attachment to the cannula and use. After use, the disc is counter-rotated to permit the cannula, mounted onto the disc, to be longitudinally retracted completely within the barrel to a proximal position in which the cannula is permanently locked by stopping the disc against further movement.
Again, the device disclosed in FF-A-2 686 242 comprises an outer, tubular housing, wherein a double-ended cannula or needle is located for longitudinal axial sliding movement with respect to the housing. Specifically, the double-ended needle is mounted onto a needle carrier having a formation protruding in such a way to be accessible from outside the housing. The needle carrier, as well as the needle mounted thereon, is slidable within the housing between a first distal position, wherein the needle projects from the housing and is exposed (e.g. for drawing blood) and a second, retracted proximal position, wherein the needle is safely located within the housing.
A basic common disadvantage to all the "two-position" arrangements considered in the foregoing is due to the fact that they generally require the needle to be a separate part of the whole arrangement, which should be generally packaged separately under sterile conditions and then assembled onto the holder just prior to use.
Consequently, the need exists of providing such a holder, wherein the needle can be pre-assembled by the manufacturer, thus dispensing with the need for the user of obtaining a new needle, removing any needle sterility caps or similar arrangements and finally screwing the needle onto the holder.
The underlying problem of the invention is to provide an improved safety needle holder fully satisfying that need.